Show that in a quadrilateral ABCD `AB+BC+CD+DA gt AC + BD`

Explanation

To prove that in a quadrilateral ABCD, the sum of the lengths of the sides is greater than the sum of the lengths of the diagonals, we need to show that:

\[ AB + BC + CD + DA > AC + BD \]

### Step-by-Step Solution:

1. **Consider Triangle ABC**:
- In triangle ABC, by the triangle inequality, we have:
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